Esterified dicarboxylic acid and its use

Abstract

The present invention specifies an esterified dicarboxylic acid of the general formula <IMAGE> in which RI is an aliphatic hydrocarbon group with 7-21 carbon atoms, RII is a hydrocarbon radical with 2-6 carbon atoms and A is an alkylene oxide group derived from an alkylene oxide with 2-4 carbon atoms. Particularly preferred are compounds in which A relates to a group derived from ethylene oxide and in which RII is -CH=CH- or the phenylene group -C6H4-. The compound exhibits selective properties when used in the flotation of oxide and salt type minerals.

We claim: 
     
       1. A process for the froth flotation of oxide minerals and salt minerals which comprises carrying out the froth flotation in the presence as a collector reagent of an esterified dicarboxylic acid having the general formula ##STR16## in which R 1  is aliphatic hydrocarbon having from seven to twenty-one carbon atoms, R 2  is hydrocarbon having from two to six carbon atoms and A is oxyalkylene having from two to four carbon atoms. 
     
     
       2. A process according to claim 1 in which A is oxyethylene. 
     
     
       3. A process according to claim 1 in which R 2  is --CH═CH-- or phenylene --C 6  H 4  --. 
     
     
       4. A process according to claim 1 in which the esterified dicarboxylic acid is used in conjunction with a water-insoluble polar secondary collector reagent. 
     
     
       5. A process according to claim 4 in which the water-insoluble polar secondary collector reagent is an alkylene oxide adduct having the formula:   R.sub.3 (A).sub.p.sbsb.1 OH     in which R 3  is hydrocarbon having from eight to twenty two carbon atoms, A is oxyalkylene derived from an alkylene oxide having from two to four carbon atoms and p 1  is a number from 1 to 6.   
     
     
       6. A process according to claim 5 in which R 3  is aliphatic or alkylaryl. 
     
     
       7. A process according to claim 4 in which the polar secondary collector reagent is an ester having the formula: ##STR17## in which R 4  is hydrocarbon having from seven to twenty one carbon atoms, A is oxyalkylene derived from an alkylene oxide having from two to four carbon atoms, p 2  is a number from 0 to 6, and Y is alkyl having from one to four carbon atoms or hydrogen.